Process for the continuous production of an optically active carbonyl compound by asymmetric hydrogenation of a prochiral α,β-unsaturated carbonyl compound with hydrogen in the presence of a homogeneous rhodium catalyst that has at least one chiral ligand, wherein a liquid reaction mixture comprising the prochiral α,β-unsaturated carbonyl compound is subjected in a first, backmixed reactor to a gas/liquid two-phase hydrogenation, and the liquid reaction mixture is then further hydrogenated in a second reactor, wherein the prochiral α,β-unsaturated carbonyl compound is employed in the first reactor in a concentration from 3% to 20% by weight. The process allows a high total conversion to the prochiral α,β-unsaturated carbonyl compound.

The present invention relates to a method for producing a 3-methylcycloalkenone compound and a method for producing muscone. In the presence of a zirconium oxide catalyst, a diketone represented by the following general formula (1):

##STR00001##

wherein in formula (1), n represents 8, 9, 10, 11 or 12,
is subjected to a vapor-phase intramolecular condensation reaction, whereby a 3-methylcycloalkenone compound can be produced with high reaction efficiency. When a 3-methylcyclopentadecenone compound produced by this method is hydrogenated in a known manner, muscone can be produced efficiently.

The present invention relates to a method for producing a 3-methylcycloalkenone compound and a method for producing muscone. In the presence of a zirconium oxide catalyst, a diketone represented by the following general formula (1):

##STR00001##

wherein in formula (1), n represents 8, 9, 10, 11 or 12,
is subjected to a vapor-phase intramolecular condensation reaction, whereby a 3-methylcycloalkenone compound can be produced with high reaction efficiency. When a 3-methylcyclopentadecenone compound produced by this method is hydrogenated in a known manner, muscone can be produced efficiently.

The present invention relates to a method for producing a 3-methylcycloalkenone compound and a method for producing muscone. In the presence of a zirconium oxide catalyst, a diketone represented by the following general formula (1):

##STR00001##

wherein in formula (1), n represents 8, 9, 10, 11 or 12,
is subjected to a vapor-phase intramolecular condensation reaction, whereby a 3-methylcycloalkenone compound can be produced with high reaction efficiency. When a 3-methylcyclopentadecenone compound produced by this method is hydrogenated in a known manner, muscone can be produced efficiently.

The inventive concepts disclosed and/or claimed herein relate generally to catalysts and, more particularly, but not by way of limitation, to a heterogeneous, metal-free hydrogenation catalyst containing frustrated Lewis pairs. In one non-limiting embodiment, the heterogeneous, metal-free catalyst comprises hexagonal boron nitride (h-BN) having frustrated Lewis pairs therein.

The inventive concepts disclosed and/or claimed herein relate generally to catalysts and, more particularly, but not by way of limitation, to a heterogeneous, metal-free hydrogenation catalyst containing frustrated Lewis pairs. In one non-limiting embodiment, the heterogeneous, metal-free catalyst comprises hexagonal boron nitride (h-BN) having frustrated Lewis pairs therein.

The inventive concepts disclosed and/or claimed herein relate generally to catalysts and, more particularly, but not by way of limitation, to a heterogeneous, metal-free hydrogenation catalyst containing frustrated Lewis pairs. In one non-limiting embodiment, the heterogeneous, metal-free catalyst comprises hexagonal boron nitride (h-BN) having frustrated Lewis pairs therein.

The present invention discloses a process for preparation of white curcumin from purified curcuminoids. The curcuminoids are obtained by solvent extraction and crystallization of dried turmeric powder. The autoclave is charged with ethyl acetate and the 95% purity curcuminoids mixture is added to and stirred for uniformity at room temperature. 5% (w/w) of 10% palladium carbon is added to the reaction mixture and allowed for hydrogenation in the presence of hydrogen gas at 2 lbps pressure and stirred continuously for 15 hours. Once the reaction is completed, the reaction mixture is filtered and washed with ethyl acetate. The ethyl acetate is distilled off and crude mass is stirred with water to obtain a solid precipitate. Finally, the solid obtained is filtered and dried to pale brown crystals of white curcumin. White curcumin is encapsulated with beta-cyclodextrin, which exhibited increased bioavailability. White curcumin also exhibited anti-oxidant and chemopreventive activities.

The present invention discloses a process for preparation of white curcumin from purified curcuminoids. The curcuminoids are obtained by solvent extraction and crystallization of dried turmeric powder. The autoclave is charged with ethyl acetate and the 95% purity curcuminoids mixture is added to and stirred for uniformity at room temperature. 5% (w/w) of 10% palladium carbon is added to the reaction mixture and allowed for hydrogenation in the presence of hydrogen gas at 2 lbps pressure and stirred continuously for 15 hours. Once the reaction is completed, the reaction mixture is filtered and washed with ethyl acetate. The ethyl acetate is distilled off and crude mass is stirred with water to obtain a solid precipitate. Finally, the solid obtained is filtered and dried to pale brown crystals of white curcumin. White curcumin is encapsulated with beta-cyclodextrin, which exhibited increased bioavailability. White curcumin also exhibited anti-oxidant and chemopreventive activities.

A reactor for performing a gas/liquid biphasic high-pressure reaction with a foaming medium, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone and a zone of limited backmixing, wherein the backmixed zone and the zone of limited backmixing are consecutively traversable by the reaction mixture, wherein the backmixed zone comprises means for introducing gas and liquid and a gas outlet and also comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the gas, and the zone of limited backmixing comprises a reaction product outlet, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a riser tube whose lower end is arranged within the backmixed zone and whose upper end opens into the zone of limited backmixing so that liquid from the backmixed zone can ascend into the zone of limited backmixing via the riser tube, wherein flow into the zone of limited backmixing enters from below. The reactor is configured such that the high-pressure reaction space is optimally utilized and contamination of workup steps or subsequent reactions arranged downstream of the high-pressure reaction with foam is substantially avoided. The invention further relates to a process for performing a continuous gas/liquid biphasic high-pressure reaction in the reactor.